Narrative:

I began my preflight inspection of the airplane, and a thin fog began to develop. I hurried to depart before the fog prevented me from doing so. At XA50, when I taxied out, I listened to the AWOS, and while I did listen to the information, it did not register in my mind that the report indicated the airport was actually IFR. As I went through the before takeoff check, again my thought was to depart VFR, based on my initial observation that the airport was VFR. At the same time, another turbojet aircraft began to taxi out, and my thoughts turned to departing as quickly as possible so as not to delay the other aircraft. During the takeoff roll, visibility was good (more than 1 1/2 mi, even though the AWOS reported 3/4 mi) and at 20-25 ft AGL we were completely out of the fog in clear conditions. It was at this point that I realized I had just departed VFR when technically the airport was reporting IFR conditions. Basically, I believe that the human element is the most predominant factor in this situation. My initial observation upon arrival at the airport was VFR with clear conditions. Mentally, that observation did not change, even after listening to AWOS during taxi. The actual conditions were not that bad, and therefore did not trigger a change in my thought process either. The fact remains though, that I still departed VFR while the airport was reporting IFR conditions. No safety hazards were involved in terms of other aircraft. The turbojet was the only other traffic at the airport and departed several mins behind me (with an IFR clearance). We both went our separate ways very safely.

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Original NASA ASRS Text

Title: A PVT PLT, MADE A VFR DEP FROM SHD DURING IMC CONDITIONS.

Narrative: I BEGAN MY PREFLT INSPECTION OF THE AIRPLANE, AND A THIN FOG BEGAN TO DEVELOP. I HURRIED TO DEPART BEFORE THE FOG PREVENTED ME FROM DOING SO. AT XA50, WHEN I TAXIED OUT, I LISTENED TO THE AWOS, AND WHILE I DID LISTEN TO THE INFO, IT DID NOT REGISTER IN MY MIND THAT THE RPT INDICATED THE ARPT WAS ACTUALLY IFR. AS I WENT THROUGH THE BEFORE TKOF CHK, AGAIN MY THOUGHT WAS TO DEPART VFR, BASED ON MY INITIAL OBSERVATION THAT THE ARPT WAS VFR. AT THE SAME TIME, ANOTHER TURBOJET ACFT BEGAN TO TAXI OUT, AND MY THOUGHTS TURNED TO DEPARTING AS QUICKLY AS POSSIBLE SO AS NOT TO DELAY THE OTHER ACFT. DURING THE TKOF ROLL, VISIBILITY WAS GOOD (MORE THAN 1 1/2 MI, EVEN THOUGH THE AWOS RPTED 3/4 MI) AND AT 20-25 FT AGL WE WERE COMPLETELY OUT OF THE FOG IN CLR CONDITIONS. IT WAS AT THIS POINT THAT I REALIZED I HAD JUST DEPARTED VFR WHEN TECHNICALLY THE ARPT WAS RPTING IFR CONDITIONS. BASICALLY, I BELIEVE THAT THE HUMAN ELEMENT IS THE MOST PREDOMINANT FACTOR IN THIS SIT. MY INITIAL OBSERVATION UPON ARR AT THE ARPT WAS VFR WITH CLR CONDITIONS. MENTALLY, THAT OBSERVATION DID NOT CHANGE, EVEN AFTER LISTENING TO AWOS DURING TAXI. THE ACTUAL CONDITIONS WERE NOT THAT BAD, AND THEREFORE DID NOT TRIGGER A CHANGE IN MY THOUGHT PROCESS EITHER. THE FACT REMAINS THOUGH, THAT I STILL DEPARTED VFR WHILE THE ARPT WAS RPTING IFR CONDITIONS. NO SAFETY HAZARDS WERE INVOLVED IN TERMS OF OTHER ACFT. THE TURBOJET WAS THE ONLY OTHER TFC AT THE ARPT AND DEPARTED SEVERAL MINS BEHIND ME (WITH AN IFR CLRNC). WE BOTH WENT OUR SEPARATE WAYS VERY SAFELY.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.